Existing unitized post tension systems for concrete masonry structures have until now required special other construction to address larger wall widths over approximately eight inches, to address horizontal decks and to address structural grade beams. The existing taught systems did not easily accommodate those needs in a unitized post tension system.
The prior art unitized post tension systems address methods and systems to rapidly build structures, including walls with for use as flat deck, wider wall systems and large grade beams. Recent unitized post tension systems facilitated improvements to traditional construction systems and their limitations. The recent systems do not require special skills to construct; does not need water and power; do not require elaborate bracing; provides immediate occupancy or use; needs no curing time; and are re-useable if desired since it is not destroyed when disassembled and moved. While the recent systems are improvements to decrease the time to build or rebuild areas with minimal skilled labor and provide a far superior and more consistent strength structure than the traditional mortar constructed structure, these systems still have room for improved devices and configurations to meet known shortcomings. The problems and limitations of the prior art unitized post tension systems are addressed generally for the use as flat deck, wider wall systems and large grade beams. In the building industry, the masonry, precast concrete and poured in place, tilt-up wall systems often accompany a building type—industrial, commercial, and hi-rise residential—where floor and roof decks are utilized. For example, motel and hotels and office buildings, strip malls and the like will incorporate precast decks or poured in place steel sheet metal and concrete to provide floors and roof decks. Therefore an alternative flat decking means from the unitized post tension system is desirable.
The unitized post tension system has also found acceptance in the southern building needs in Mississippi and Louisiana. In those locations, the rapid build system afforded by unitized post tension systems still had restrictions with the need for grade beams to be used in the quasi-marsh areas in cooperation with posts or pilings. Here the spans were of such lengths that some consideration for higher tension strength in the grade beams presented some challenges to the unitized post tension system. Therefore a better adapted and improved grade beam made of unitized post tension components with added features and capabilities is desirable.
The final desired improvement to unitized post tension systems is not an intuitively obvious need. In the concrete masonry unit (CMU) building systems, the approximately eight inch wide block is the main component. However, over the years, the need for ten inch, twelve inch and larger widths became evident. These were addressed by the industry to provide wide base walls. However, these wider block came at a price: they required all new, wider molds to produce; they were much heavier and usually required two people to lift and transport, and they often needed additional tooling and accessories to match the wider widths. Therefore, it is desirable to build wider, higher capacity wall systems from the unitized post tension components. The new system that addresses this will save the cost of molds, added labor and employee fatigue, and added costs for the wider blocks. However, the new use of the unitized post tension components would need to be as strong or even stronger than the CMU counterparts. These problems or limitations of the desires for the use as flat deck, wider wall systems and large grade beams are described below.
Historically, no known devices have attempted to address the problem as stated. The building industry has made little progress for a unitized, post tension system so improvements to the recent unitized post tension systems have not yet been attractive to promotion of the technology. Even so, blocks have required very special and often complex configurations to even handle rods and plates and then they have taught only limit rods in special blocks. One such device is an instant levy block system. This is a complex, specially made block for constructing a levy, comprising a plurality of blocks, a plurality of connecting pegs, and a plurality of stakes. Each part is uniquely designed and made whereas the novel technology uses a commonly made block designed for the common bars and bolts. Another block device is a masonry block with an embedded plate. The concrete masonry block has an external plate or plates that are anchored through the concrete masonry block. The external plates are cast into the concrete masonry block in the mold during casting. These plates and metal pieces are not taught as being part of a post tensioning system now shown cast within the hollow cavities as addressed by the improved novel technology.
Another device for construction is a modular pre-cast construction block system with a wall subsystem and a foundation subsystem. The wall subsystem has a number of wall units having cavities and pre-stressed tension cables are cast therein the cavity. This teaches precast walls and pass through cable which are specially made, require water, and are not readily re-useable like the novel technology. A somewhat re-useable system includes long rods that extend through apertures in the specially cast block and the precast structures. No description of pre or post tensioning is taught or claimed. The configuration of special length rods, special blocks, special plates and a complex system that requires powered equipment to construct is unlike the novel technology.
One known mortarless wall structure comprises columns of preformed, lightweight, stacked blocks, with the columns of blocks connected to each other by elongated, vertically oriented, support beams. Preferably, the wall structure is operatively connected to a structure by one or more brackets. The beams and blocks are special configuration, not readily available and with limited uses. These are complex and do not anticipate the novel technology.
An interlocking, mortar less system is accomplished by some other devices. However, none of them are found to show a structural unitized post tensioning system as described for the novel technology in the materials below. An example of one such interlocking device is a block of concrete or the like for use in constructing a mortar less wall. The device provided includes a spaced parallel pair of upright sidewalls having flat bottoms and tops and bearing integral block interlocking connectors and various configurations on their opposite ends. The sidewalls are integrally connected by means of these configurations. This is not the configuration taught by the novel technology. Another motarless system is a set of superimposed building blocks with vertically spaced flat bars inter-fitted with the blocks and studs inserted through one bar and then threaded into engagement with bars of lower blocks.
None of the prior art found with a rigorous search teaches all the features and capabilities of the novel technology. As far as known, there are no systems at the present time which fully meet the need for a unitized, post-tensioned masonry block structure with the described shortfalls which are now resolved by the present novel technology. It is believed that this system is made with component parts, is built with simple tools, and provides a much stronger structure than prior art devices and systems.